关键词: 振动与波 , 发动机 , 振动模态 , 有限元 , 模态分析

Abstract: To research the dynamic properties of military engines, experiment analysis and finite element calcula?tion were adopted. Based on the correct 3-D solid models of body, crankshaft, cylinder head and crankcase, an integrated engine model was built in this paper. Virtual materials were introduced to simulate the stiffness and damping features of the joint surfaces between those four elements, which are difficult to obtain either theoreti?cally or experimentally. Property parameters of the virtual materials were gradualy modified until FEM result of the engine’s vibration modal became consistent with the experiment result. Thus, the validity of the finite ele?ment model of the engine was proved, which paves the way for further engine dynamic simulation research.

Key words: vibration and wave , engine , vibration modal , finite element , modal analysis